First use ghost mode and jump to the bunk(like the one under which D99 is hiding) in Sausagehead guy's cell. When the guard is facing to D99's left, signal D99(L). He will come and hide under it. Next, a guard will start patrolling the area. Jump to his bullet proof vest using ghost mode and when he reaches the mid landing of the stairs, use ghost mode and jump to vest of the guard crouching in the ceiling. Use ghost mode and open the latch. The guard falls down and will head to the upper row of cells. Jump to the Soda can in the mid landing of the stairs and then proceed to the the power socket/manipulator thingy. Signal D99 the moment the patrolling guard is out of the way. He hides under the stairs. Now wait for the guards to reach the landing in the stairs and jump to either one of their vests. Find your way to the bell in Sausageheadguy's cell and ring it to distract the guard on the ground level. While he is checking out the hole in wall and the other guard is patrolling above, use ghost mode and jump to the core near the latches and Signal D99. He climbs up into the ceiling. Close the latch and then move to the core on the other side. Jump to the toilet above and signal him to make roll over there. Once the guard arrives, jump to his vest and then jump to the bunk in the empty cell and signal him over. Keep moving D99 until you reach the latch in Rock Band guys cells. Open it and play the drums to make the guard fall down. Make D99 climb up to the upper row and proceed to the exit.
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